Australian Marc Leishman raced out of the blocks on his way to a two-stroke lead but several big names were lined up within striking distance after the first round at the BMW Championship outside Chicago on Thursday.
Leishman holed 10 birdies to match his career-low score on the PGA Tour, posting a nine-under-par 62 in ideal conditions at Conway Farms in Lake Forest.
His compatriot Jason Day, the 2015 champion, was nursing a stiff back but carded a 64 that was matched by Americans Charley Hoffman and Jamie Lovemark, while Jordan Spieth was among a group who shot 65s.
Rory McIlroy, needing a top-four finish to make the Tour Championship, is 10 shots off the lead after a one-over 72.
The world number six got off to a terrible start, having to take a drop and running up a double-bogey six on the opening hole.
He would get it back to level by the turn thanks to three birdies and a bogey, but his back nine was a case of gains offset by dropped shots in another frustrating outing.
To cap it all he three putted the closing par five 18th to sign for a round of 72.
Spieth heads the FedExCup standings – and the race for the $10 million bonus awarded to the overall season champion, which McIlroy secured last year.
Leishman is seventh in the standings after finishing third in the previous event in the tour’s playoff series and he continued his good form, honing in on the pins with precise approach shots to set up numerous birdie opportunities. Only two of his birdies came from outside 12 feet.
“Confidence is high and hopefully I can just ride the wave,” Leishman told reporters.
“I hit the ball really well but probably more importantly putted really well, made the opportunities I gave myself.
“When your putter is rolling well it takes pressure off the rest of your game. All you’re thinking about is making as many as possible and it was nice to make 10 today.”
Spieth, meanwhile, moved steadily up the leaderboard to a share of fifth.
“Bogey-free was really solid today, considering some of the spots I hit it,” said the British Open champion.
“Good putting early. I only hit one of my first five greens and was (two-under). I feel I stole a couple there, which is rare to feel like you scored better than you played.
“I’m going to have to hit more greens in regulation but it was nice around the greens and I feel pretty comfortable.”
Rickie Fowler hit six consecutive birdies from the 12th hole for his 65, while Justin Thomas, Spieth’s closest pursuer in the FedExCup standings, carded 67 for a share of 14th.
